Pig cell transplant decision delayed

Removing the need for insulin injections is the aim of some researchers who want to transplant insulin-producing pig cells into people with juvenile diabetes (Image: iStockphoto)

Research into transplanting whole animal organs into humans should be banned for five years, Australia's health advisory body has recommended.

But it has not yet decided whether to allow animal cells and tissues to be transplanted into humans.

At a meeting held in Perth this week the National Health and Medical Research Council (NHMRC) said it needed more time to consider the risks and regulatory implications of approving the use of animal cells and tissues to treat human disease.

"The council has said that there should be no clinical research into animal to human whole organ transplants for another five years," said NHMRC's chief executive officer Professor Alan Pettigrew. "Because the risks are too great according to our current understanding of research."

But the NHMRC said that cellular and tissue therapies had a "lower potential risk of infection and higher expected benefit to humans" than whole organ transplants. And that it needed more information before deciding on research guidelines.

The NHMRC has also advised against using non-human primates, like baboons, in animal-to-human transplants.

Uncertain times for some research

The move to delay a decision about the cell and tissue transplants disappointed Professor Bernie Tuch of Sydney's Prince of Wales Hospital, who wants to transplant insulin-producing pig cells into people with juvenile or type 1 diabetes.

Tuch, who has already been knocked back by the NHMRC for such research, said success in transplanting insulin-producing pig cells in animal experiments supported moving to human studies.

Questions remain over the risk of using pigs cells to treat human diseases (Image: USDA)

"Pilot studies of insulin-producing pig cells into humans are going to be needed in the not so distant future," he told ABC Science Online.

"Without any clear direction of when or if such therapies could be developed in Australia ... [this] leaves people in the uncertain situation of knowing what direction to follow."

Tuch said his comments were based on the limited information available in this week's NHMRC statement.

"The communiqué from the NHMRC, essentially not giving a green light for the possible use of cell therapies for conditions such as type 1 diabetes, sends a message to those in the research field who are trying to develop such therapies that life will continue to be difficult," said Tuch.

He said researchers like him would either have to bide their time, producing more data to try to convince the NHMRC to allow the research, or move into other areas of cell therapies that were not being blocked, such as those using stem cells.

Support for caution

But infectious diseases expert Professor Peter Collignon of the Canberra Hospital, who believes the risk of transferring animal viruses to humans outweighs the benefits of the treatments, welcomed the NHMRC announcement.

"I think this particular finding from the NHMRC seems to be a sensible decision," he told ABC Science Online.

The anti-vivisection lobby group Australian Association for Humane Research welcomed the five-year ban on whole-organ transplants but said transplanting animal cells and tissues still presented a risk and was equally unethical.

The group also objected to ongoing pre-clinical xenotransplantation research on animals and said it would be preferable to put scarce resources into alternative research approaches.

Behind the decision

The NHMRC took advice from its Xenotransplantation Working Group, which conducted two rounds of public consultation.

"[The NHMRC] recognises this decision is a really, really important one for the community and they don't want to rush it," said working group and NHMRC member, Dr Kerry Breen.